Stop setting `auto_join` on space child events (#8863)
Stop setting `auto_join` on space child events (#8863)

It's not a specified property and not even used.
matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk,matrix-org/matrix-react-sdk